summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/admin-guide')
-rw-r--r--Documentation/admin-guide/acpi/cppc_sysfs.rst2
-rw-r--r--Documentation/admin-guide/cifs/todo.rst44
-rw-r--r--Documentation/admin-guide/cifs/usage.rst8
-rw-r--r--Documentation/admin-guide/devices.txt3
-rw-r--r--Documentation/admin-guide/features.rst2
-rw-r--r--Documentation/admin-guide/hw_random.rst5
-rw-r--r--Documentation/admin-guide/kernel-parameters.rst5
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt44
-rw-r--r--Documentation/admin-guide/kernel-per-CPU-kthreads.rst16
-rw-r--r--Documentation/admin-guide/pm/amd-pstate.rst2
-rw-r--r--Documentation/admin-guide/sysrq.rst11
11 files changed, 80 insertions, 62 deletions
diff --git a/Documentation/admin-guide/acpi/cppc_sysfs.rst b/Documentation/admin-guide/acpi/cppc_sysfs.rst
index e53d76365aa7..36981c667823 100644
--- a/Documentation/admin-guide/acpi/cppc_sysfs.rst
+++ b/Documentation/admin-guide/acpi/cppc_sysfs.rst
@@ -75,4 +75,4 @@ taking two different snapshots of feedback counters at time T1 and T2.
delivered_counter_delta = fbc_t2[del] - fbc_t1[del]
reference_counter_delta = fbc_t2[ref] - fbc_t1[ref]
- delivered_perf = (refernce_perf x delivered_counter_delta) / reference_counter_delta
+ delivered_perf = (reference_perf x delivered_counter_delta) / reference_counter_delta
diff --git a/Documentation/admin-guide/cifs/todo.rst b/Documentation/admin-guide/cifs/todo.rst
index 2646ed2e2d3e..9a65c670774e 100644
--- a/Documentation/admin-guide/cifs/todo.rst
+++ b/Documentation/admin-guide/cifs/todo.rst
@@ -2,7 +2,8 @@
TODO
====
-Version 2.14 December 21, 2018
+As of 6.7 kernel. See https://wiki.samba.org/index.php/LinuxCIFSKernel
+for list of features added by release
A Partial List of Missing Features
==================================
@@ -12,22 +13,22 @@ for visible, important contributions to this module. Here
is a partial list of the known problems and missing features:
a) SMB3 (and SMB3.1.1) missing optional features:
+ multichannel performance optimizations, algorithmic channel selection,
+ directory leases optimizations,
+ support for faster packet signing (GMAC),
+ support for compression over the network,
+ T10 copy offload ie "ODX" (copy chunk, and "Duplicate Extents" ioctl
+ are currently the only two server side copy mechanisms supported)
- - multichannel (partially integrated), integration of multichannel with RDMA
- - directory leases (improved metadata caching). Currently only implemented for root dir
- - T10 copy offload ie "ODX" (copy chunk, and "Duplicate Extents" ioctl
- currently the only two server side copy mechanisms supported)
+b) Better optimized compounding and error handling for sparse file support,
+ perhaps addition of new optional SMB3.1.1 fsctls to make collapse range
+ and insert range more atomic
-b) improved sparse file support (fiemap and SEEK_HOLE are implemented
- but additional features would be supportable by the protocol such
- as FALLOC_FL_COLLAPSE_RANGE and FALLOC_FL_INSERT_RANGE)
-
-c) Directory entry caching relies on a 1 second timer, rather than
- using Directory Leases, currently only the root file handle is cached longer
- by leveraging Directory Leases
+c) Support for SMB3.1.1 over QUIC (and perhaps other socket based protocols
+ like SCTP)
d) quota support (needs minor kernel change since quota calls otherwise
- won't make it to network filesystems or deviceless filesystems).
+ won't make it to network filesystems or deviceless filesystems).
e) Additional use cases can be optimized to use "compounding" (e.g.
open/query/close and open/setinfo/close) to reduce the number of
@@ -92,23 +93,20 @@ t) split cifs and smb3 support into separate modules so legacy (and less
v) Additional testing of POSIX Extensions for SMB3.1.1
-w) Add support for additional strong encryption types, and additional spnego
- authentication mechanisms (see MS-SMB2). GCM-256 is now partially implemented.
+w) Support for the Mac SMB3.1.1 extensions to improve interop with Apple servers
+
+x) Support for additional authentication options (e.g. IAKERB, peer-to-peer
+ Kerberos, SCRAM and others supported by existing servers)
-x) Finish support for SMB3.1.1 compression
+y) Improved tracing, more eBPF trace points, better scripts for performance
+ analysis
Known Bugs
==========
See https://bugzilla.samba.org - search on product "CifsVFS" for
current bug list. Also check http://bugzilla.kernel.org (Product = File System, Component = CIFS)
-
-1) existing symbolic links (Windows reparse points) are recognized but
- can not be created remotely. They are implemented for Samba and those that
- support the CIFS Unix extensions, although earlier versions of Samba
- overly restrict the pathnames.
-2) follow_link and readdir code does not follow dfs junctions
- but recognizes them
+and xfstest results e.g. https://wiki.samba.org/index.php/Xfstest-results-smb3
Misc testing to do
==================
diff --git a/Documentation/admin-guide/cifs/usage.rst b/Documentation/admin-guide/cifs/usage.rst
index 5f936b4b6018..aa8290a29dc8 100644
--- a/Documentation/admin-guide/cifs/usage.rst
+++ b/Documentation/admin-guide/cifs/usage.rst
@@ -81,7 +81,7 @@ much older and less secure than the default dialect SMB3 which includes
many advanced security features such as downgrade attack detection
and encrypted shares and stronger signing and authentication algorithms.
There are additional mount options that may be helpful for SMB3 to get
-improved POSIX behavior (NB: can use vers=3.0 to force only SMB3, never 2.1):
+improved POSIX behavior (NB: can use vers=3 to force SMB3 or later, never 2.1):
``mfsymlinks`` and either ``cifsacl`` or ``modefromsid`` (usually with ``idsfromsid``)
@@ -715,6 +715,7 @@ DebugData Displays information about active CIFS sessions and
Stats Lists summary resource usage information as well as per
share statistics.
open_files List all the open file handles on all active SMB sessions.
+mount_params List of all mount parameters available for the module
======================= =======================================================
Configuration pseudo-files:
@@ -864,6 +865,11 @@ i.e.::
echo "value" > /sys/module/cifs/parameters/<param>
+More detailed descriptions of the available module parameters and their values
+can be seen by doing:
+
+ modinfo cifs (or modinfo smb3)
+
================= ==========================================================
1. enable_oplocks Enable or disable oplocks. Oplocks are enabled by default.
[Y/y/1]. To disable use any of [N/n/0].
diff --git a/Documentation/admin-guide/devices.txt b/Documentation/admin-guide/devices.txt
index 839054923530..94c98be1329a 100644
--- a/Documentation/admin-guide/devices.txt
+++ b/Documentation/admin-guide/devices.txt
@@ -2704,6 +2704,9 @@
...
185 = /dev/ttyNX15 Hilscher netX serial port 15
186 = /dev/ttyJ0 JTAG1 DCC protocol based serial port emulation
+
+ If maximum number of uartlite serial ports is more than 4, then the driver
+ uses dynamic allocation instead of static allocation for major number.
187 = /dev/ttyUL0 Xilinx uartlite - port 0
...
190 = /dev/ttyUL3 Xilinx uartlite - port 3
diff --git a/Documentation/admin-guide/features.rst b/Documentation/admin-guide/features.rst
index 8c167082a84f..7651eca38227 100644
--- a/Documentation/admin-guide/features.rst
+++ b/Documentation/admin-guide/features.rst
@@ -1,3 +1,3 @@
.. SPDX-License-Identifier: GPL-2.0
-.. kernel-feat:: $srctree/Documentation/features
+.. kernel-feat:: features
diff --git a/Documentation/admin-guide/hw_random.rst b/Documentation/admin-guide/hw_random.rst
index d494601717f1..bfc39f1cf470 100644
--- a/Documentation/admin-guide/hw_random.rst
+++ b/Documentation/admin-guide/hw_random.rst
@@ -14,10 +14,9 @@ into that core.
To make the most effective use of these mechanisms, you
should download the support software as well. Download the
-latest version of the "rng-tools" package from the
-hw_random driver's official Web site:
+latest version of the "rng-tools" package from:
- http://sourceforge.net/projects/gkernel/
+ https://github.com/nhorman/rng-tools
Those tools use /dev/hwrng to fill the kernel entropy pool,
which is used internally and exported by the /dev/urandom and
diff --git a/Documentation/admin-guide/kernel-parameters.rst b/Documentation/admin-guide/kernel-parameters.rst
index 102937bc8443..4410384596a9 100644
--- a/Documentation/admin-guide/kernel-parameters.rst
+++ b/Documentation/admin-guide/kernel-parameters.rst
@@ -218,8 +218,3 @@ bytes respectively. Such letter suffixes can also be entirely omitted:
.. include:: kernel-parameters.txt
:literal:
-
-Todo
-----
-
- Add more DRM drivers.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 505af40e97bc..31b3a25680d0 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -888,9 +888,9 @@
memory region [offset, offset + size] for that kernel
image. If '@offset' is omitted, then a suitable offset
is selected automatically.
- [KNL, X86-64, ARM64, RISCV] Select a region under 4G first, and
- fall back to reserve region above 4G when '@offset'
- hasn't been specified.
+ [KNL, X86-64, ARM64, RISCV, LoongArch] Select a region
+ under 4G first, and fall back to reserve region above
+ 4G when '@offset' hasn't been specified.
See Documentation/admin-guide/kdump/kdump.rst for further details.
crashkernel=range1:size1[,range2:size2,...][@offset]
@@ -901,25 +901,27 @@
Documentation/admin-guide/kdump/kdump.rst for an example.
crashkernel=size[KMG],high
- [KNL, X86-64, ARM64, RISCV] range could be above 4G.
+ [KNL, X86-64, ARM64, RISCV, LoongArch] range could be
+ above 4G.
Allow kernel to allocate physical memory region from top,
so could be above 4G if system have more than 4G ram
installed. Otherwise memory region will be allocated
below 4G, if available.
It will be ignored if crashkernel=X is specified.
crashkernel=size[KMG],low
- [KNL, X86-64, ARM64, RISCV] range under 4G. When crashkernel=X,high
- is passed, kernel could allocate physical memory region
- above 4G, that cause second kernel crash on system
- that require some amount of low memory, e.g. swiotlb
- requires at least 64M+32K low memory, also enough extra
- low memory is needed to make sure DMA buffers for 32-bit
- devices won't run out. Kernel would try to allocate
+ [KNL, X86-64, ARM64, RISCV, LoongArch] range under 4G.
+ When crashkernel=X,high is passed, kernel could allocate
+ physical memory region above 4G, that cause second kernel
+ crash on system that require some amount of low memory,
+ e.g. swiotlb requires at least 64M+32K low memory, also
+ enough extra low memory is needed to make sure DMA buffers
+ for 32-bit devices won't run out. Kernel would try to allocate
default size of memory below 4G automatically. The default
size is platform dependent.
--> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB)
--> arm64: 128MiB
--> riscv: 128MiB
+ --> loongarch: 128MiB
This one lets the user specify own low range under 4G
for second kernel instead.
0: to disable low allocation.
@@ -2449,7 +2451,7 @@
between unregistering the boot console and initializing
the real console.
- keepinitrd [HW,ARM]
+ keepinitrd [HW,ARM] See retain_initrd.
kernelcore= [KNL,X86,IA-64,PPC]
Format: nn[KMGTPE] | nn% | "mirror"
@@ -3996,9 +3998,9 @@
vulnerability. System may allow data leaks with this
option.
- no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES] Disable paravirtualized
- steal time accounting. steal time is computed, but
- won't influence scheduler behaviour
+ no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES,RISCV] Disable
+ paravirtualized steal time accounting. steal time is
+ computed, but won't influence scheduler behaviour
nosync [HW,M68K] Disables sync negotiation for all devices.
@@ -5313,6 +5315,12 @@
Dump ftrace buffer after reporting RCU CPU
stall warning.
+ rcupdate.rcu_cpu_stall_notifiers= [KNL]
+ Provide RCU CPU stall notifiers, but see the
+ warnings in the RCU_CPU_STALL_NOTIFIER Kconfig
+ option's help text. TL;DR: You almost certainly
+ do not want rcupdate.rcu_cpu_stall_notifiers.
+
rcupdate.rcu_cpu_stall_suppress= [KNL]
Suppress RCU CPU stall warning messages.
@@ -5598,7 +5606,8 @@
Useful for devices that are detected asynchronously
(e.g. USB and MMC devices).
- retain_initrd [RAM] Keep initrd memory after extraction
+ retain_initrd [RAM] Keep initrd memory after extraction. After boot, it will
+ be accessible via /sys/firmware/initrd.
retbleed= [X86] Control mitigation of RETBleed (Arbitrary
Speculative Code Execution with Return Instructions)
@@ -6926,6 +6935,9 @@
pause after every control message);
o = USB_QUIRK_HUB_SLOW_RESET (Hub needs extra
delay after resetting its port);
+ p = USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT
+ (Reduce timeout of the SET_ADDRESS
+ request from 5000 ms to 500 ms);
Example: quirks=0781:5580:bk,0a5c:5834:gij
usbhid.mousepoll=
diff --git a/Documentation/admin-guide/kernel-per-CPU-kthreads.rst b/Documentation/admin-guide/kernel-per-CPU-kthreads.rst
index 993c2a05f5ee..b6aeae3327ce 100644
--- a/Documentation/admin-guide/kernel-per-CPU-kthreads.rst
+++ b/Documentation/admin-guide/kernel-per-CPU-kthreads.rst
@@ -243,13 +243,9 @@ To reduce its OS jitter, do any of the following:
3. Do any of the following needed to avoid jitter that your
application cannot tolerate:
- a. Build your kernel with CONFIG_SLUB=y rather than
- CONFIG_SLAB=y, thus avoiding the slab allocator's periodic
- use of each CPU's workqueues to run its cache_reap()
- function.
- b. Avoid using oprofile, thus avoiding OS jitter from
+ a. Avoid using oprofile, thus avoiding OS jitter from
wq_sync_buffer().
- c. Limit your CPU frequency so that a CPU-frequency
+ b. Limit your CPU frequency so that a CPU-frequency
governor is not required, possibly enlisting the aid of
special heatsinks or other cooling technologies. If done
correctly, and if you CPU architecture permits, you should
@@ -259,7 +255,7 @@ To reduce its OS jitter, do any of the following:
WARNING: Please check your CPU specifications to
make sure that this is safe on your particular system.
- d. As of v3.18, Christoph Lameter's on-demand vmstat workers
+ c. As of v3.18, Christoph Lameter's on-demand vmstat workers
commit prevents OS jitter due to vmstat_update() on
CONFIG_SMP=y systems. Before v3.18, is not possible
to entirely get rid of the OS jitter, but you can
@@ -274,7 +270,7 @@ To reduce its OS jitter, do any of the following:
(based on an earlier one from Gilad Ben-Yossef) that
reduces or even eliminates vmstat overhead for some
workloads at https://lore.kernel.org/r/00000140e9dfd6bd-40db3d4f-c1be-434f-8132-7820f81bb586-000000@email.amazonses.com.
- e. If running on high-end powerpc servers, build with
+ d. If running on high-end powerpc servers, build with
CONFIG_PPC_RTAS_DAEMON=n. This prevents the RTAS
daemon from running on each CPU every second or so.
(This will require editing Kconfig files and will defeat
@@ -282,12 +278,12 @@ To reduce its OS jitter, do any of the following:
due to the rtas_event_scan() function.
WARNING: Please check your CPU specifications to
make sure that this is safe on your particular system.
- f. If running on Cell Processor, build your kernel with
+ e. If running on Cell Processor, build your kernel with
CBE_CPUFREQ_SPU_GOVERNOR=n to avoid OS jitter from
spu_gov_work().
WARNING: Please check your CPU specifications to
make sure that this is safe on your particular system.
- g. If running on PowerMAC, build your kernel with
+ f. If running on PowerMAC, build your kernel with
CONFIG_PMAC_RACKMETER=n to disable the CPU-meter,
avoiding OS jitter from rackmeter_do_timer().
diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 1cf40f69278c..9eb26014d34b 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -361,7 +361,7 @@ Global Attributes
``amd-pstate`` exposes several global attributes (files) in ``sysfs`` to
control its functionality at the system level. They are located in the
-``/sys/devices/system/cpu/amd-pstate/`` directory and affect all CPUs.
+``/sys/devices/system/cpu/amd_pstate/`` directory and affect all CPUs.
``status``
Operation mode of the driver: "active", "passive" or "disable".
diff --git a/Documentation/admin-guide/sysrq.rst b/Documentation/admin-guide/sysrq.rst
index 51906e47327b..2f2e5bd440f9 100644
--- a/Documentation/admin-guide/sysrq.rst
+++ b/Documentation/admin-guide/sysrq.rst
@@ -75,10 +75,19 @@ On other
submit a patch to be included in this section.
On all
- Write a character to /proc/sysrq-trigger. e.g.::
+ Write a single character to /proc/sysrq-trigger.
+ Only the first character is processed, the rest of the string is
+ ignored. However, it is not recommended to write any extra characters
+ as the behavior is undefined and might change in the future versions.
+ E.g.::
echo t > /proc/sysrq-trigger
+ Alternatively, write multiple characters prepended by underscore.
+ This way, all characters will be processed. E.g.::
+
+ echo _reisub > /proc/sysrq-trigger
+
The :kbd:`<command key>` is case sensitive.
What are the 'command' keys?